ip step modefy

 

void _CalcIpv6Addr(UCHAR *pucIpv6Addr, IPV6_POOL_S *pIpv6Pool, ULONG ulIndex)
{
    DWORD ulTmp   = 0;
    DWORD ulFirst = 0;
    DWORD ulLast  = 0;

    memcpy(pucIpv6Addr, pIpv6Pool->ucaFirstIpv6, 16);
    memcpy(&ulFirst, pucIpv6Addr + (pIpv6Pool->ucModBit - 1) / 16 * 2 - 2, 4);
    ulFirst = htonl(ulFirst);
   
    ulTmp = (pIpv6Pool->ucStep
             * pow2(2, (pIpv6Pool->ucModBit - 1) / 16 * 16 + 16 - pIpv6Pool->ucModBit)
             * ulIndex);
   
    ulLast = htonl(ulFirst + ulTmp);   
    memcpy(pucIpv6Addr + (pIpv6Pool->ucModBit - 1) / 16 * 2 - 2, &ulLast, 4);
}

 

ULONG CalcGroupIp(IP_POOL_S *pGroupPool, ULONG ulGroupIndex)
{
     ULONG ulStep    = pGroupPool->ucStep * (ULONG)(pow2(2, (32 - pGroupPool->ucModBit)));
     ULONG ulGroupIp = pGroupPool->ulFirstIp + ulStep * ulGroupIndex;
     return ulGroupIp;
}

 

ULONG pow2(ULONG ulArg1, ULONG ulAgr2)
{
     ULONG ulVal = 1;
     ULONG i;

     for (i = 0; i < ulAgr2; i++)
     {
   ulVal = ulVal * ulArg1;
     }

     return ulVal;
}